A Study on the Flow Mechanism Within Centrifugal Impeller Channels

Investigations concerning the flow patterns within centrifugal impeller channels have been made for many years. However, many of the problems remain unresolved about the secondary flow and the loss production mechanism within impeller channels. In the present study, measurements of the flow mechanism within impeller channels under the off-design conditions were performed by employing yaw probes to compare the results with those at the design point. The impellers with straight radial blades employed in the present study were of the same configuration except the shroud profiles which made diffusion ratios different from each other. From the present results, it became clear that the loss production mechanisms and the flow patterns within impeller channels were essentially unvaried both under design and off-design operations. The results thus obtained by the present study were furthermore compared with the others to examine the reliability of these results.